Chap - a SIMD graphics processor

Abstract

Special purpose processing systems designed for specific applications can provide extremely high performance at moderate cost. One such processor is presented for executing graphics and image processing algorithms as the basis of a digital film printer. Pixels in the system contain four parallel components: RGB for full color and an alpha channel for retaining transparency information. The data path of the processor contains four arithmetic elements connected through a crossbar network to a tessellated scratchpad memory. The single instruction, multiple data stream (SIMD) processor executes instructions on four pixel components in parallel. The instruction control unit (ICU) maintains an activity stack for tracking block-structured code, using data-dependent activity flags for conditional disabling subsets of the ALUs. Nested loops and if-then-else constructs can be programmed directly, with the ICU disabling and reenabling ALUs on the basis of their individual status bits.

References

1. 1 Barnes, G., et all, The ILLIAC IV Computer. IEEE Transactions on Computers Vol C-17, No 8 (August 1968), pp 746-757.
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3. 3 Kubo, M., Taguchi, Y., Agusa, K., Ohno, Y., A multi-microprocessor system for three dimensional color graphics. Proc of IFIP 80, 1980.
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Index Terms

• Computer systems organization

  • Architectures

    • Parallel architectures

      • Single instruction, multiple data

• Computing methodologies

  • Computer graphics

    • Graphics systems and interfaces

    • Rendering

      • Rasterization

• Hardware

  • Communication hardware, interfaces and storage

    • Displays and imagers

  • Integrated circuits

    • Logic circuits